The invention concerns a hydrodynamic brake having a rotor and a stator which are arranged in a fixed housing having inlet and outlet connections for hydraulic fluid.
The use of such hydrodynamic brakes as energy converting means in connection with heat exchangers in wind-power installations is known. In such systems, it is desirable to be able to adapt the torque characteristic of the hydrodynamic brake to that of the wind-power installation or other power source. Such adaptation can be achieved by, for example, altering the state of fill of the housing. However, in the case of the said applications and with closed-cycle systems, such change in the state of fill suffers from the disadvantage that it is difficult to control. The brake cannot be regulated at the high pressure that normally prevails in such systems.
Variation of the torque characteristic by means of baffles which are inserted between the rotor and the stator is also known. Such baffles have the disadvantage that they are pressed against the stator by the pressure forces occurring in the brake. These pressure forces are difficult to control. Furthermore, the constructions concerned are relatively complicated. A further known way of influencing the torque characteristic consists in altering the axial distance between the stator and the rotor within the common housing. In this arrangement, a relatively large displacement is necessary in order to enable the so-called K-value of the hydrodynamic brake to be adapted to suit the wind wheel or other power source.